Extensible Dressings

ABSTRACT

The present invention generally relates to dressings such as bandages or tapes having improved extensibility and conformability to human skin and joints.

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims the benefit of the earlier filing date ofU.S. provisional patent application 62/483,992, filed Apr. 11, 2017, theentirety of which application is hereby incorporated by reference hereinas if fully set forth herein.

FIELD OF THE INVENTION

The present invention generally relates to dressings such as bandages ortapes having improved extensibility and conformability to human skin andjoints. In certain embodiments, the present invention relates todressings that include, at least one layer of material, a portion ofwhich layer of material includes a plurality of material free regionsextending through the thickness of the portion. In at least oneexemplary embodiment, the plurality of the material free regions isarranged in the form of a pattern of concentric slitted annuli having acommon center point, P, the pattern of concentric slitted annuli having,relative to the center point P, a radially innermost concentric annulusand a radially outermost concentric annulus respectively having theshortest and the longest diameters.

BACKGROUND OF THE INVENTION

Dressings such as bandages and tapes for applying to and/or covering theskin have been known for some time. Such dressings have gained wideacceptance for closing minor wounds, protecting minor wounds and/orcovering abrasions. In some instances, microporous or breathable,bandages or tapes have been developed and are used either to cover minorwounds or wounds that have been partially healed.

While such dressings have been greatly improved over the years in that,for example, they have incorporated microporous materials allowing thewound to breath and permitting water vapor to escape from the wound,hence, reducing chances of wound maceration, there remains a need fordressing which provide improved extensibility and elasticity of thedressing such that the dressing will cover and accommodate thedimensional contours of skin or tissues and move with (i.e.,accommodating movement of) that portion of the skin or tissues coveredby or in contact with the dressing, particularly in the situation wherethe dressing covers or is in contact with areas of the human tissueassociated with jointed regions such as the joints of the fingers,ankles or knees. Accordingly, in order for a dressing to provide theaforementioned attributes, the dressing should also be able todynamically conform to and with changing three dimensional contour ofthe skin or tissue surfaces to which it is applied.

The dressing should also be conformable to, or provide sufficientdrapability, over the area of the human skin tissue to which it isadhered.

It is, therefore, an aspect of the present invention to providedressings that may be used to cover, protect wounds and facilitate woundhealing. It is a further aspect of the present invention to providebandages and tapes that conform to a wounded area of the skin and haveimproved extensibility, elasticity and conformability for bettercoverage of movable areas such as joints. Other aspects of the presentinvention will be readily apparent from the ensuing description andclaims.

SUMMARY OF THE INVENTION

In one embodiment, the present invention relates to a dressingcomprising:

-   -   a layer of non-cellulosic material having:        -   (i) a length direction (L), a width direction (W), and a            thickness direction (T) respectively defining axes in three            mutually orthogonal directions, the length direction (L) and            the width direction W defining a horizontal plane (“the LW            plane”), and the thickness direction (T) defining an up-down            direction or a vertical direction relative to the LW plane,            the layer of material having a thickness taken in the            thickness direction; and        -   (ii) a plurality of material free regions, each of the            material free regions extending through the thickness of at            least a portion of the layer of material and the plurality            of the material free regions being arranged in the form of a            pattern of concentric slitted annuli having a center            point (P) in the LW plane, the pattern of concentric slitted            annuli having, relative to center point P, a radially            innermost concentric annulus and a radially outermost            concentric annulus, the innermost and the outermost            concentric annuli respectively having the shortest and the            longest diameters,    -   wherein the plurality of the material free regions is arranged        end to end, separated by a plurality of spatial intervals, such        that any material free region ln located in any concentric        annulus I subtends a non-zero valued angle, α_(ln), at the        center point P, where n represents the number identifying a        material free region in an annulus having material free regions        arranged numerically consecutively in such annulus,    -   wherein the sum of the non-zero valued angles subtended by the        plurality of the material free regions at the center point P,        within any one of the concentric annuli, is less than 360        degrees, and    -   wherein the material free regions of any one of the concentric        annuli are in a radially staggered relation with respect to the        material free regions in any adjacent inner and/or adjacent        outer concentric annulus.

The present invention also relates to methods of using/applying thedressings of the present invention, including the disclosed embodiments,on skin surfaces covering jointed areas (or areas prone to movement) ofhuman or mammalian bodies.

BRIEF DESCRIPTION OF THE DRAWINGS

An embodiment of this invention will now be described in greater detail,by way of illustration only, with reference to the accompanyingdrawings, in which:

FIG. 1 shows a perspective view of a layer of material including aplurality of material free regions arranged in the form of a pattern ofconcentric slitted annuli;

FIG. 2 shows a planar view of a layer of material including a pluralityof material free regions arranged in the form of a pattern of concentricslitted annuli;

FIGS. 2A shows a planar view of a pattern of concentric slitted annuli;

FIG. 2B shows another planar view of a pattern of concentric slittedannuli of FIG. 2A with each material free region labeled;

FIG. 3A shows a perspective view of the layer of material of FIG. 1 in aflat configuration in the plane of the layer of material with materialfree regions of the pattern of concentric slitted annuli of FIG. 2A in aclosed position;

FIG. 3B shows a perspective view of the layer of material of FIG. 1 inan expanded configuration resulting from application of a force in thethickness direction T of the layer of material with the material freeregions of the pattern of concentric slitted annuli of FIG. 3A in anopen position;

FIG. 3C shows a perspective view of the layer of material of FIG. 3Breturned to the flat configuration in the plane of the dressing uponremoval of the force in the thickness direction T of the layer ofmaterial with material free regions of the pattern of concentric slittedannuli of FIG. 2A returned to the closed position;

FIG. 4A shows a planar view of the pattern of concentric slitted annuliof FIG. 2A with centerlines of each annulus of the concentric slittedannuli drawn-in;

FIG. 4B shows a planar view of a pattern of concentric slitted annuli;

FIG. 5 shows a planar view of a pattern of concentric slitted annuli;

FIG. 6 is an exploded view of a dressing of the present inventionshowing an additional layer in between the layer of material of thepresent invention and a releasable layer;

FIG. 7 is an exploded view of a dressing of the present inventionshowing the layer of material of the present invention in between abacking layer and a releasable layer; and

FIG. 8 shows a perspective view of another dressing in accordance withan exemplary embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The dressing of the present invention can comprise, consist of, orconsist essentially of the essential elements and limitations of theinvention described herein, as well as any of the additional or optionalfeatures, components, or limitations described herein.

The term “comprising” (and its grammatical variations) as used herein isused in the inclusive sense of (and, interchangeably with the terms)“having” or “including” and not in the exclusive sense of “consistingonly of.” The terms “a” and “the” as used herein are understood toencompass the plural as well as the singular.

As used here in the specification and the claims, the terms “skin” and“tissue” are interchangeable and refer to mammalian skin.

As used here in the specification and the claims, the term“dermatologically acceptable” means suitable for use in contact withskin tissue without undue toxicity, incompatibility, instability oradverse reaction with the skin tissue.

As used here in the specification and the claims, the terms “proximate”,“neighboring”, “adjacent”, and any variants thereof, are usedinterchangeably in connection with the present invention.

As used here in the specification and the claims, the term “annulus”denotes a circular profile/shape, e.g., a circle, or a non-circularprofile/shape, such as an ellipse, or any polygonal shape thatapproximates a circle or an ellipse shape.

As used here in the specification and the claims, the term “concentriccenterline”, of any given concentric annulus, denotes an imaginary linethat is either coincident with a circumference (e.g., passes throughmidpoints of an annular path) of the concentric annulus or an imaginaryline that intersects at least a segment of each of a plurality ofmaterial free regions that are arranged end to end at a spatial, in someembodiments predetermined, interval to form the concentric annulus.

As used herein, the terms “visual inspection” or “visually inspected”means inspection with the unaided eye (excepting standard correctivelenses adapted to compensate for near-sightedness, farsightedness, orstigmatism, or other corrected vision) in lighting at least equal to theillumination of a standard 75 watt incandescent white light bulb at adistance of about 0.25 meter.

All documents incorporated herein by reference, by portion or in theirentirety, are only incorporated herein to the extent that they are notinconsistent with this specification.

In certain embodiments, the present invention as disclosed herein may bepracticed in the absence of any component, element (or group ofcomponents or elements) or method step which is not specificallydisclosed herein.

An embodiment of this invention will now be described in greater detail,by way of illustration only, with reference to the accompanyingdrawings. Referring to the drawings in detail, wherein like referencenumerals indicate like elements throughout, there is shown in

FIGS. 1-5, a dressing, generally designated with reference numeral 10,in accordance with an exemplary embodiment of the present invention.

Layer of Material

Referring to FIG. 1, in an exemplary embodiment, the dressing 10includes a layer of material 12 having a length direction (L), a widthdirection (W), and a thickness direction (T) respectively defining axesin three mutually orthogonal directions, the length direction (L) andthe width direction W jointly defining a horizontal plane (“the LWplane”), and the thickness direction T defining an up-down direction ora vertical direction relative to the LW plane and top and bottom (skinfacing) surfaces. In one embodiment, as illustrated in FIG. 1, the layerof material 12 has a thickness 14 taken in the thickness direction T. Inaddition to the circular shape indicated in the figures, the layer ofmaterial can take the form of any number of shapes, including but notlimited to, rectangular, oval, ovoid, or oblong etc.

In certain embodiments, the layer of material is formed from cellulosicmaterial, the cellulosic material comprising fibers having a length todiameter ratio of greater than, or equal to, 600.

In other embodiments, the layer of material is formed fromnon-cellulosic or regenerated cellulose material. The term“non-cellulosic” with respect to the material means that the materialcontains less than 10 wt %, optionally containing less than 5 wt %,optionally containing less than 1 wt %, optionally containing less than0.1 wt %, or optionally containing 0 wt %, of cellulosic components orfibers. The term “regenerated cellulose” with respect to the materialmeans the material contains less than 10 wt %, optionally containingless than 5 wt %, optionally containing less than 1 wt %, optionallycontaining less than 0.1 wt %, or optionally containing 0 wt %, ofnon-regenerated cellulose components or fibers. Suitable materialsinclude, but are not limited to, (or selected from or selected from thegroup consisting of) polyurethanes, polyethylene, polyisobutadiene,polyisobutylene, neoprene, polyamides, polyesters (such as polyethyleneterephthalate (PET), polybutylene terephthalate (PBT) and mixturesthereof), polyether polyesters, non-hydrophilic polyether-polyamides,plasticised polyvinyl chloride, styrene-butadiene block copolymers,styrene-isoprene block copolymer, polyacrylates, methacrylic copolymers,polypropylene, rayon, rayon/polyester blends and mixtures thereof. Incertain embodiments, the material is a dermatologically acceptablematerial.

Material Free Regions

In one embodiment, as illustrated in FIGS. 1 and 2A, the layer ofmaterial 12 of the dressing 10 includes a plurality of material freeregions 16 each of which extends through the thickness 14 of at least aportion of the layer of material 12. The term “material free” or “freeof material” as used herein means regions or areas of the layer ofmaterial that are free of material or substantially free of materialsuch that the continuity of the material is disrupted or such regions orareas are devoid of material and include, and interchangeable with, butnot limited to, cuts, holes, slits (or slitted) or openings in thematerial. In certain embodiments, the distinct material free regions 16are sigmoidal in shape and include such distinct regions which may notbe discernable by the naked eye (i.e., viewing without the aid ofoptical lenses which magnify the field of view); examples of suchinclude ultra-thin cuts or slits formed in the layer of material 12 bycutting the layer of material 12 with a knife thickness of about 1 μm toabout 15 μm, or a laser having laser thickness of about 10 μm to 1000μm. The material free regions can be in the form of any number ofshapes. In certain embodiments, as illustrated in FIGS. 1-3 and FIG. 6,these material free regions 16 in the layer of material 12 can be in theform of individual arcs or sigmoidal slits, respectively.

In addition to lasers and knifes, the material free regions may also beincorporated into the layer of material 12 during the formation of thelayer of material 12 such as by water jet cutting, high pressure steamcutting and the like.

In one embodiment, as illustrated in FIGS. 2B and 2C, the plurality ofthe material free regions 16 is arranged as slits in the form of apattern of slitted concentric annuli 18 having a center point (P) in theLW plane of the layer. In one embodiment, as in FIG. 2A, the pattern ofconcentric slitted annuli 18 is depicted as having eight annuli labeledA to H from innermost concentric annulus A to the outermost concentricannulus H. However, it should be understood that the number of annuli inthe pattern of concentric slitted annuli 18 can be any number above 1,including 2, 3, 4, 5, and so on. Depending on the particular applicationand/or specific nature of the material used for the dressing 10 thepattern of concentric slitted annuli 18 may include any number ofconcentric annuli, all within the purview of one skilled in the art.

Referring to FIGS. 1-2B, in one exemplary embodiment, the layer ofmaterial 12 includes a pattern of concentric slitted annuli 18 in whicheach concentric annulus includes a number n of the plurality of thematerial free regions 16. The number n of material free regions in anygiven concentric annulus can be any suitable number so long as it wouldresult in a dressing having at least one or more of the propertiesdescribed in this application and so long as the innermost concentricannulus A comprises at least two material free regions 16. In oneembodiment, as illustrated in FIG. 2B, the same number of the materialfree regions 16 exists in each of the concentric annuli A-H. However, itshould be understood that the number n of material free regions 16 mayvary among the concentric annuli of the pattern of concentric slittedannuli 18. In some embodiments, the number n of the material freeregions 16 ranges from 2 to 25, optionally from 2 to 18, optionally from2 to 7, optionally from 3 to 7.

In some embodiments, the number n of the material free regions 16 in anygiven concentric annulus ranges from 3 to 10.

Referring to FIG. 2A, in one embodiment, the plurality of the materialfree regions 16 is arranged end to end separated by spatial intervals24. In particular, the plurality of the material free regions 16 isarranged sequentially along an annular path such that the material freeregions 16 are separated by spatial intervals 24 from each other andeach of the material free regions 16 subtends an angle, α, (e.g., α₁ andα₂) at the center point P of the pattern of concentric slitted annuli18. The angle α that is subtended at the center point P by any givenmaterial free regions 16 can have a value ranging from about 20° toabout 177°, optionally from 20° to 90°, optionally from 30° to 60°.Typically, the sum of the angles subtended at the center point P by theplurality of the material free regions 16 within any given concentricannulus is less than 360 degrees but more than 0 degrees. This ensurespresence of the spatial intervals 24 between the material free regions16.

In at least one embodiment, as further illustrated in FIG. 2B, thematerial free regions 16 of any one of the concentric annuli 18 aredisposed in radially staggered relation (i.e., not aligned) with respectto the material free regions 16 of any adjacent inner and/or adjacentouter concentric annulus. The material free region Al of the innermostconcentric annulus A, for example, is in a staggered relation withproximate material free regions B1 and B10 of adjacent interveningconcentric annulus B. Similarly, the material free region C1 ofintervening concentric annulus C, for example, is in a staggeredrelation with proximate material free regions D1 and D10 of adjacentintervening concentric annulus D and also with proximate material freeregions B1 and B10 of adjacent intervening concentric annulus B.Similarly, the material free region H1 of outermost concentric annulusH, for example, is in a staggered relation with proximate material freeregions G1 and G2 of adjacent intervening concentric annulus G. Thus,each of the material free regions of any concentric annulus that isadjacent to a radially inner concentric annulus and a radially outerconcentric annulus is adjacent, and staggered with respect, to fourmaterial free regions, two in the adjacent radially inner concentricannulus and two in the adjacent radially outer concentric annulus. Incontrast, each of the material free regions in the innermost concentricannulus or the outermost concentric annulus is only adjacent, andstaggered with respect, to two material free regions in a neighboringconcentric annulus since each of the innermost and outermost concentricannuli is adjacent to only one concentric annulus.

The staggered arrangement described above is further illustrated in FIG.2A, where any material free region 16 of any one of the concentricannuli of the pattern of concentric slitted annuli 18 has an axis ofsymmetry which bisects such material free region 16 and thecorresponding material free region 16 of the radially innermostconcentric annulus to which it is aligned. Such axis of symmetry alsobisects the angle subtended by such material free region 16 and thecorresponding material free region 16 of the radially innermost annulusto which it is aligned at the center point P. For example, the materialfree region 1C of concentric annulus C has an axis of symmetry 28 whichbisects material free region 1C and also bisects material free region 1Aof innermost concentric annulus A with which it is aligned; the axis ofsymmetry 28 also bisects angle α₁ subtended by the material free regions1C and 1A at the center point P. Similarly, material free region 1D ofconcentric annulus D has an axis of symmetry 30 which bisects materialfree region 1D and also bisects material free region 1B of innermostconcentric annulus B with which it is aligned; the axis of symmetry 30also bisects angle α₂ subtended by the material free regions 1D and 1Bat the center point P. The axis of symmetry 28 of one set of alignedmaterial free regions 16 is staggered relative to axis of symmetry 30 ofthe other set of aligned material free regions 16 by an angle φ.Generally, the axis of symmetry 28 of aligned material free regions 1Aand 1C of concentric annuli A and C and the axis of symmetry 30 ofaligned material free regions 1B and 1D of concentric annuli B and D arestaggered relative to one another by an angle φ which has a value thatgenerally falls within a range specified by the equation: 0°<φ<(α₁+α₂),wherein α_(i) is the angle subtended by the material free regions 1A and1C at the center point P and α₂ is the angle subtended by the materialfree regions 1B and 1D at the center point P. The angle φ can have anysuitable non-zero value, including values ranging from about 5° to 40°,optionally from about 5° to 30°, optionally from about 5° to 25°,optionally from about 5° to 20°, optionally from about 10° to 20°. Forany intervening concentric annulus between the innermost concentricannulus A and outermost concentric annulus H, any material free region16 is proximate to two material free regions 16 located in an adjacentconcentric, radially inner annulus and two material free regions 16located in an adjacent concentric, radially outer annulus with respectto the intervening concentric annulus. Accordingly, as shown in theembodiment of FIG. 2B, material free region B8 of intervening concentricannulus B is proximate to material free regions A8 and A9 of theinnermost concentric annulus A and material free regions C8 and C9 ofthe intervening concentric annulus C. Moreover, material free region B8of intervening concentric annulus B has an axis of symmetry (bisectingthe angle subtended by the material free region B8 at the center pointP) that is staggered by angle φ relative to each of the respective axesof symmetry of proximate material free regions A8, A9, C8 and C9.

Accordingly:

-   -   (a) any material free region ln located in any concentric        annulus I subtends a non-zero valued angle α_(ln) at the center        point P and has an axis of symmetry that bisects the non-zero        valued angle α_(ln);    -   (b) any material free region Kn located in any concentric        annulus K that is adjacent to concentric annulus I and proximate        to material free region ln, subtends a non-zero valued angle        α_(Kn) at the center point P and has an axis of symmetry that        bisects the non-zero valued angle α_(Kn);    -   (c) the axis of symmetry of the material free region ln is        staggered by an angle φ from the axis of symmetry of the        material free region Kn; and    -   (d) the angle φ has a value that falls within a range specified        by the equation: 0°<φ<(α_(ln)+α_(Kn))        where n represents the number identifying a material free region        in an annuli having material free regions arranged numerically        consecutively in such annuli (as shown in FIG. 2B, for example,        in the case of F1 through F10 for annulus F).

By way of illustration, for n =8, the material free region F8 of annulusF would subtend an angle α_(F8) at the center point P and a materialfree region adjacent and proximate to F8, such as E8 (or E9), ofadjacent annulus E would likewise subtend angle α_(E8) (or α_(E9) in thecase of E9) at the center point P and the axis of symmetry of F8 and E8(or E9) would, respectively, bisect angles α_(F8) and α_(E8) (or α_(E9)in the case of E9). It should be understood that material free regionsG8 and G9 of annulus G (adjacent to F) would also be considered adjacentand proximate to F8 and, similarly, subtending and bisecting theirrespective angles α_(G8) and α_(G9) at the center point P.

As noted elsewhere in this application, the angle φ can have anysuitable non-zero value, including values ranging from 5 optionally fromabout 5° to 40°, optionally from about 10° to 40°, optionally from 10°to 30°.

As evident in FIG. 2, the concentric annuli of the pattern of concentricslitted annuli 18 have radii that increase in value relative to thecenter point P of the pattern of concentric slitted annuli 18 movingfrom the radially innermost concentric annulus A (having the shortestradius) to the radially outermost concentric annulus H (having thelongest radius). In other words, in any pattern of concentric slittedannuli 18 the innermost concentric annulus A will have the shortestdiameter (e.g., diameter 20) and the outermost concentric annulus H willhave the longest diameter (e.g., diameter 22).

Referring to FIG. 4A, each concentric annulus of the concentric annuliof the pattern of concentric slitted annuli 18 is radially spaced apartfrom any adjacent inner or outer concentric annulus with respect to theconcentric annulus (see reference numeral 34). Also, each concentricannulus has a concentric centerline defined therethrough as indicated,for example, by the dashed concentric centerline referenced by numeral32 in FIG. 4A. The term concentric centerline, of any given concentricannulus, denotes an imaginary line that is either coincident with acircumference (e.g., passes through midpoints of an annular path as inFIG. 4A) of the concentric annulus of the pattern of concentric slittedannuli 18 or an imaginary line that intersects at least a segment ofeach of the plurality of the material free regions 16 that are arrangedend to end separated by a spatial interval to form the concentricannulus (as shown by the dashed concentric centerline referenced bynumeral 32 for the innermost concentric annulus in FIG. 5). Any pair ofneighboring concentric centerlines of adjacent concentric annuli isradially spaced apart from each other by a distance that is thedifference between the lengths of the respective radii of the adjacentconcentric annuli or the difference between the distances of therespective centerlines of the adjacent concentric annuli as measuredfrom the center point P (e.g., FIG. 4A, reference numeral 34).

In one embodiment, as illustrated in FIG. 4A, the radial distances 34between neighboring pairs of concentric centerlines of successive pairsof neighboring annuli of the pattern of concentric slitted annuli 18 canbe substantially equal to each other or different from each other. Inother embodiments, any pair of neighboring annuli is separated by aradial spacing 34 (measured as a distance between concentric centerlinesof the pair of neighboring annuli) that varies among any different pairsof centerlines of other successive pairs of neighboring annuli of thepattern of concentric slitted annuli 18. In one embodiment, the radialspacing 34 between pairs of neighboring centerlines of neighboringannuli has a value that is at its minimum between the innermostconcentric annulus and its neighboring concentric annulus and increasesradially outwardly to its maximum value between the outermost concentricannulus and its neighboring concentric annulus. In one embodiment, asillustrated in FIG. 4B, the radial spacing 34 between pairs ofneighboring centerlines of neighboring annuli has a value that is at itsmaximum between the innermost concentric annulus and its neighboringconcentric annulus and, as also illustrated in FIG. 4B, the radialspacing 34 decreases radially outwardly to its minimum between theoutermost concentric annulus and its neighboring concentric annulus(compare reference numerals 34 and 34′). However, other configurationsfor the radial distances between adjacent concentric annuli arepossible. Accordingly, in some embodiments, the pattern of concentricslitted annuli 18 has a radial spacing 34 between concentric centerlinesof successive pairs of neighboring annuli that varies among differentpairs of neighboring concentric annuli such that the magnitudes ofsuccessive radial spacings are not necessarily arranged in an ascendingor a descending order but in some random order.

Typically, the radial distance 34 between a pair of concentric annuli ofthe pattern of concentric slitted annuli 18 has a value that ranges from0.01 inches to 1.0 inches, optionally from 0.01 inches to 0.5 inchesfrom 0.01 inches to 0.25 inches; 0.01 inches to 0.125 inches.

An ideal dressing should provide an optimal healing environment that canpromote new cell growth and/or healing when appropriate. Additionally,or in other situations, the dressing may be required to protect the siteof application from trauma, to administer medicine, to absorb exudate,to keep wounds, pressure sores, ulcers, warts or lesions clean, and/orto stop bleeding. Also, depending on its location on the body surface,the environment of the wound, pressure sore, ulcer, wart or lesion, maybe subjected to frequent stress, strain, or a combination of stress andstrain as the three dimensional contour of the covered skin surface siteor the skin surface around the covered site changes in response tomovements of tissues beneath the skin surface. Areas of the mammaliantissue, including human tissue, such as skin surface, associated withjointed regions of the body, such as the joints of the fingers, anklesor knees, can exhibit pronounced movements and changes in their threedimensional contours. Accordingly, in situations where a dressing coversor is in contact with these areas of the body, if the dressing is notable to expand and/or stretch to accommodate changes in body geometryresulting from the movements of the tissues beneath it and/or around it,the likelihood that the dressing would cause discomfort to the wearer orfail by coming off altogether and/or cause trauma to the site ofapplication are all increased, as the dressing counteract the forcesresulting from the movements of the tissue surface at or around the sitewhich it covers or is in contact with. Accordingly, in order for adressing to provide one or more of the aforementioned desiredattributes, the dressing may need to not only be able to adhere to theskin surface for a relatively extended amount of time, but also be ableto dynamically conform to changing three dimensional contour of the skinsurface to which it is applied. Accordingly, in order to provide thedynamic conformability benefit, the dressing of the present invention isdesigned to be resiliently, freely expandable to a range of threedimensional configurations when one force or a plurality of forces aredirected at or applied to the dressing having the pattern of concentricslitted annuli 18.

In any of the above-described embodiments, the dressing 10 is applied toa mammalian tissue or skin so as to, for example, cover or contact awound, a pressure sore, an ulcer, a wart, a lesion, or a skin surface.In such embodiments, any movement of the skin surface at or around suchcovered or contacted area can cause and exert a force on the dressing 10in the thickness direction T thereof. The concentric pattern of annuli18 is configured such that it is resiliently, freely expandable in thethickness direction T of the dressing 10 (i.e., in the direction of theforce) between an initial substantially flat configuration in the LWplane of the dressing 10 and an expanded configuration in the thicknessdirection T of the dressing 10 (see FIGS. 3A and 3B), the concentricpattern of annuli 18 includes material free regions 16 that are arrangedsuch that, when any movement of the skin surface at or around an areacovered or contacted by the dressing 10 causes and exerts a force on thedressing 10, (see FIGS. 3A-3C), the material free regions 16 freelychange from their initial closed configuration (or an initialsubstantially closed configuration), such as in FIG. 3A, to their openconfiguration (shown as 16′ in FIG. 3B), causing expansion of theconcentric pattern of annuli 18 in the thickness direction T, from theinitial flat configuration in the LW plane to the expanded configurationin the thickness direction T of the dressing 10 (as illustrated in FIG.3B), wherein once the force is no longer being exerted on the dressing10 in the thickness direction T the material free regions 16 freelyreturn to their initial closed (or substantially closed) configuration(see FIGS. 3A and 3C), causing the pattern of concentric 18 to freelyreturn to its initial substantially flat configuration in the LW plane(as shown in FIG. 3C). The term “freely” as used herein means that thematerial used to form the layer of material 12 will not swell so as torestrict or inhibit the opening or closing of the material free regions16 and/or, once any releasable layer is removed, the layer of material12 is not attached to any additional layer or substrate so as restrictor inhibit the opening or closing of the material free regions 16. Theterm “closed”, “closed position” or “closed configuration”, as usedherein with respect to the material free regions 16, means that thematerial free regions 16 are closed or substantially closed such thatthere is no, or substantially no, visibility through the material freeregions 16 upon visual inspection. The term “open”, “open position” or“open configuration”, as used herein with respect to the material freeregions 16, means that the material free regions 16 are open such thatthere is visibility through the material free regions 16 upon visualinspection. The term “visibility” as used herein means the ability tosee and identify distinct features of animate or inanimate objects.

In one embodiment, therefore, as shown in FIGS. 3A-3C, the dressing ofthe present invention mitigates stress and/or strain at the skinsurface/dressing interface by dynamically freely expanding at least inits thickness direction to create a three-dimensional shape that isconformable to changing three dimensional contour of the skin surface towhich it is applied. In one embodiment, the dressing of the presentinvention includes a pattern of concentric slitted annuli 18 which formsa three dimensionally expansible portion of the dressing. In oneembodiment, the pattern of concentric slitted annuli 18 imparts a threedimensional expansibility to the dressing 10 by having material freeregions 16 that are resiliently openable in the thickness direction ofthe dressing to expand at least a portion of the dressing into a threedimensional configuration that is conformable to a three dimensionalcontour of the skin surface to which the dressing is applied. In oneembodiment, the material free regions 16 of the dressing 10 areresiliently freely openable in the thickness direction T of the dressingin response to an application of a force to the dressing 10, which canhappen as a result of a change in the three dimensional contour of theskin surface to which the dressing 10 is applied, to confer a threedimensional configuration to the dressing such that the dressing canconform to a changed three dimensional contour of the skin surfaceunderneath it. In some embodiments, when a force is applied to thepattern of concentric slitted annuli 18 of the dressing 10 one or moreof the material free regions 16 of the dressing 10 are resilientlyfreely opened in the thickness direction T of the dressing 10 to apercentage that is proportionate to the magnitude of the applied force.Thus, when the applied force is lessened or increased the percentage towhich the one or more material free regions 16 are opened in thethickness direction T of dressing 10 is respectively decreased orincreased.

The extent to which the dressing 10 of the present invention isexpansible in its thickness direction T can be modulated by the choiceof the materials from which the dressing 10 is made and also by thechoice of the number n of the material free regions 16 included in oneor more of the concentric annuli of the pattern of concentric slittedannuli 18. In one embodiment, as illustrated in FIG. 2C, the number n ofthe material free regions 16 is 10 and is the same across all concentricannuli of the pattern of concentric slitted annuli 18. However, otherarrangements of the material free regions 16 are also within the purviewof the present invention. Contemplated within the purview of the presentinvention are embodiments in which the number n of the material freeregions 16 varies across different concentric annuli of the pattern ofconcentric slitted annuli 18. Any suitable number of material freeregions 16 can be used in the present invention. In some embodiments,the number n of material free regions 16 in any given concentric annuluscan range from 2 to 25, optionally from 3 to 25. In some specificembodiments, the number n of material free regions 16 in any givenconcentric annulus is an integer selected from 2, 3, 4, etc., up to andincluding 25.

In certain embodiments, the pattern of concentric slitted annuli 18 areformed into the layer of material 12 so as to cover from about 50% toabout 100%, optionally at least about 75% to about 100%, optionally fromabout 90% to about 100%, or optionally 100% (or about 100%), of thesurface area of a surface (of both top and bottom planar surfaces) ofthe layer of material 12. As used herein, “cover 100% of the surfacearea of a surface of the layer of material” or “100% surface areacoverage of the surface of the layer of material” or means that thepattern of concentric slitted annuli cover the entire surface area ofthe surface of the layer of material and extend to the perimeter edgesof the layer of material 12.

The degree of extensibility with which the dressing 10 extends byexpansion in its thickness direction T can be measured using anInstru-Met & Instron 1122 & 5543 (Instru-Met Corporation, Union, NJ07083) with an ASTM D3787 Burst Fixture, including 44.5 mm ID ring clampand 25.4 mm spherical plunger where the throat of the Burst Fixture ismodified by extending it from its original length of 2.5″ to a length of3.75″ and where the springs under the screws are removed to ensureclamping forces. The MTS Test Works 4.12 F software application(Instru-Met Corporation, NJ) can also be used to aid in calculations.

Referring to FIG. 2A, in one embodiment, the dressing of the presentinvention includes spatial intervals 24 between adjacent material freeregions 16 within the same concentric annulus of the pattern ofconcentric slitted annuli 18. In one embodiment, the spatial intervals24 between material free regions 16 within the same concentric annulusare substantially identical to each other. In some embodiments, thespatial intervals 24 within the same concentric annulus of the patternof concentric slitted annuli 18 vary in their magnitudes betweendifferent pairs of adjacent material free regions 16. In otherembodiments, the spatial intervals 24 within the same concentric annulusare substantially identical in their magnitudes but vary in magnitudesbetween different concentric annuli of the pattern of concentric slittedannuli 18. In some other embodiments, the spatial intervals 24 havemagnitudes that do not only differ substantially within any givenconcentric annulus and between different concentric annuli of theconcentric pattern of concentric slitted annuli 18.

In one embodiment, as illustrated in FIG. 2A, the dressing of thepresent invention includes a plurality of spatial intervals 24 betweenmaterial free regions 16 within any given concentric annulus whereineach of the spatial intervals 24 has a size that has a minimal valuewithin the innermost concentric annulus and increases in value with eachsuccessive radially outer concentric annulus to its maximum value withinthe outermost concentric annulus of the concentric pattern of annuli 18.In one embodiment, as illustrated in FIG. 4B, each of the spatialintervals 24 within any given concentric annulus subtends an angle θ atthe center P, wherein the angle θ has a value that ranges from about 3°to 20°, optionally from about 6° to 20°. In some specific embodiments,the angle θ has a value selected from 3°, 4°, 5°, etc., up to andincluding 20°.

Referring to FIG. 2B, in one embodiment, the dressing of the presentinvention includes material free regions 16 each of which has a length36. As illustrated in FIG. 2B, each of the plurality of the materialfree regions 16 within any given concentric annulus, has a length 36that is substantially the same among the plurality of the material freeregions 16 within that concentric annulus. In one embodiment, each ofthe plurality of the material free regions 16 within any givenconcentric annulus has a length 36 that varies among differentconcentric annuli but is substantially the same among the plurality ofthe material free regions 16 within the same concentric annulus. In someembodiments, each of the material free regions 16 has a length 36 thatnot only varies among the plurality of the material free regions 16within the same concentric annulus, but also varies between differentconcentric annuli of the pattern of concentric slitted annuli 18. In oneembodiment, as illustrated in FIG. 2B, any of the material free regions16 of the dressing of the present invention has a length 36 that has aminimal value when the material free region 16 is located within theinnermost concentric annulus and increases in value with each successiveradially outer concentric annulus to a maximum value when the materialfree region 16 is located within the outermost concentric annulus.

Referring to FIGS. 2A and 5, in one embodiment, the dressing of thepresent invention includes a plurality of material free regions 16 eachof which has a shape which can be any suitable shape so long as theshape would result in a dressing having at least one or more of theproperties described elsewhere in the present application. In oneembodiment, the dressing of the present invention includes a pluralityof material free regions 16 each of which has a curvilinear shape, asigmoidal shape, a stepped shape, or any combinations thereof

Optional Components

In some embodiments, the dressing 10 further incorporates on at leastone of the top and bottom (or skin facing) surfaces of the layer ofmaterial 12, optionally on the bottom (or skin facing) surface, anadhesive to provide adherence of the dressing 10 to a tissue/skinsurface. When incorporated onto dressing 10, the adhesive is applied soas not restrict or inhibit the material free regions 16 from beingfreely movable between their initial closed configuration and openconfiguration. In general, any of a variety of pressure-sensitiveadhesives can be used with the dressing 10. Exemplary pressure-sensitiveadhesives, include pressure-sensitive adhesives that are biocompatiblewith human skin, including water soluble and water insolublepressure-sensitive adhesives and pressure-sensitive adhesives that aredispersible in an aqueous environment. Examples of commerciallyavailable dispersible pressure-sensitive adhesive include: those soldunder the trade name of HL-9415-X (available from H.B. Fuller Company).Another suitable adhesive includes about 10-75% by weight of apolyalkyloxazoline polymer, 10-75% by weight of a functional diluentcomprising a hydroxy compound or a carboxylic acid compound, and 5-50%by weight of a tackifier. Thus, suitable pressure sensitive adhesive mayvary in their compositions. Some may comprise hydrocolloids. Thehydrocolloid element used may be any substance that has a goodperformance in this utilization, as for example, sodiumcarboxymethylcellulose, pectin, xanthan gum, polysaccharides, sodium orcalcium alginates, chitosan, seaweed extract (cageenan), polyasparticacid, polyglutamic acid, hyaluronic acid or salts and derivativesthereof, among others. Hydrocolloids, such as sodiumcarboxymethylcellulose and pectin, among others, are agents that formgels as soon as they come into contact with bodily fluids, from wounds,for example. When used in adhesive bandages, these hydrocolloids arecombined with elastomers and/or adhesives. Preferably, the adhesivebandage should provide a humid environment but without saturation,cicatrisation, which is a situation suitable for acceleration of thehealing.

Other conventional adhesives known for such use in wound dressings maybe used with the dressing 10 of the present invention. For example,pressure-sensitive acrylic adhesives, including those containing a resinfor increasing adhesion, a cohesion increasing agent, an absorptionagent (preferably a polyacrylate superabsorbent, a polyacrylate saltsuperabsorbent or a mixture thereof), and/or a plasticizer andoptionally a pigment.

When applied to the dressing 10 of the present invention, thepressure-sensitive adhesive may be configured in discontinuous patterns,arranged in lines, screen, spray or any other configurations within thepurview of a person skilled in the art.

In one embodiment, as illustrated in FIG. 1, the dressing 10(optionally, including any additional layers 40 [as discussed in moredetail below]) further includes a releasable layer 38 in releasablecontact with (or releasable attachment to): i) the layer of material 12;or ii) the dressing 10 comprising the layer of material 12. In furtherembodiments, the releasable layer 38 releasably contacts and covers anyadhesive disposed on the layer of material 12. In other embodiments, thereleasable layer 38 comprises an adhesive so that the releasable layer38 adheres to the layer of material 12. In certain embodiments, thereleasable layer 38 contacts (or, is releasably attached to) the layerof material 12 or the dressing 10 while the material free regions 16 arein a closed configuration. In some embodiments, the releasable layer 17contacts (or, is releasably attached to) the layer of material 12 or thedressing 10 such that the material free regions 16 are releasablyretained in the closed configuration until such time as the releasablelayer 38 is removed from the layer of material 12 or the dressing 10.The releasable layer 38 can be comprised of any suitable material,including, for example, polyethylene, polypropylene, kraft papers,polyester or composites of any of these materials.

In one embodiment, as illustrated in FIGS. 6 and 7, the dressing 10includes one or more layers in addition to the layer of material 12disposed on the layer of material 12. In one embodiment, the dressing 10includes additional layer (or substrate layer) 40. In such embodiments,the layer of material 12 is not attached to any additional layer 40 suchthat additional layer 40 significantly restricts or inhibits the openingor closing of the material free regions 16. In certain embodiments, theadditional layer 40 may or may not incorporate the material free regions16. In embodiments where the additional layer 40 incorporates thematerial free regions 16, the material free regions 16 in the additionallayer 40 form the same or similar pattern units as the concentric annulipattern units formed by the material free regions 16 in the layer ofmaterial 12; in certain of such embodiments, the pattern units of theadditional layer 40 are also aligned with the pattern units of the layerof material 12. In another embodiment, the dressing 10 includes one ofthe one or more additional layers 40 disposed either on the surface sideof the layer of material 12 which is opposite the releasable layer 38 ordisposed between the layer of material 12 and releasable layer 38. Anyone of the one or more additional layers 40 may itself comprise a singleor multiple layers. The additional layer 40, in the form of a single ormultiple layer, may be incorporated to act as a protective backing layerfor layer of material 12 as shown in FIG. 7. Or, such additional layer40 may act as, or include, a pad layer providing absorbent and/orswelling properties as shown in FIG. 6. In certain embodiments, theadditional layer 40 comprises the material free regions 16, and/or thepattern of concentric annuli 18, of the present invention. In certainembodiments, the additional layer 40 is free of or substantially free ofthe material free regions 16 of the present invention.

In certain embodiments, when additional layer 40 acts as a pad layer,additional layer 40 includes a first surface 42 facing a first side 44of the layer of material 12, and that has a first surface area 50 and asecond surface 48 opposite the first surface 42 and facing the skin, andthat has a second surface area 52. Typically, the pad layer can beformed from open work, porous, natural or synthetic fibrous material,such as material used to form gauze. The pad layer typically contactsthe skin surface and/or wound to absorb wound exudate or excretions. Incertain embodiments, when the additional layer 40 acts as a pad layer,the additional layer 40 can be affixed either directly or indirectlylayer of material 12 so that it will not become separated from layer ofmaterial 12 during normal use.

When used as a backing layer, additional layer 40 may, in addition tothe circular shape illustrated at FIG. 7, have various other shapes,including but not limited to, rectangular, oval, ovoid, or oblong etc.In such an embodiment, the shape of the bandage and tape 10 may bedefined by the shape of additional layer 40. In some such embodiments,additional layer 40 may be thin, highly flexible or deformable,water-impervious, and clear or opaque. Generally, in some suchembodiments, the thickness of additional layer 40 is between about 0.05to 0.2 millimeter (“mm”) to achieve the forming and flexingcharacteristics desired.

In certain such embodiments, where additional layer 40 acts as a backinglayer, the material used in forming the additional layer 40 should beboth conformable to the contours of the body and flexible so as topermit free movement of the body part wearing the product. In certainembodiments, it can be a woven or nonwoven fabric, a film or a foam.Polymeric materials useful in forming backing layers include polyolefin(such as polyethylene), polyurethane, and polyvinylchloride. Otherexamples of backings include, but are not limited to, nonwoven, woven,or knitted fabrics such as cotton, polyester, polyurethane, rayon andthe like.

Polyethylene film may be optional used to form additional layer 40 whereadditional layer 40 acts as a backing layer 40, and, in such instances,particularly effective results can be achieved with stretchable,elastomeric films formed of polyurethane, which has the furtheradvantage of gas (including water vapor) transmissibility. It is to beunderstood, however, that, in such instances, other flexible, waterinsoluble polymeric films known in the art may be used. Furthermore,where additional layer 40 is used as a backing layer, additional layer40 may be formed from closed-cell polymeric foam, particularly one withan integral skin covering the side of the closed-cell polymeric foamfacing away from the skin of the user. In certain such embodiments, foamlayers formed of polyurethane or polyethylenes are suitable, while otherpolymeric foams having similar properties may be used. In otherembodiments, where additional layer 40 is used as a backing layer,additional layer 40 may be made from other polyolefins, vinylpolyethylene acetate, textile non-woven fabrics, rubber, or othermaterials known in the adhesive article art. In certain embodiments,polymers used to form additional layer 40 where additional layer 20 actsas a backing layer generally have viscosity of from about 500 to 500,000centipoises at temperatures of about 190°C., or from about 1,000 to30,000 centipoises at temperatures of about 190°C., or from about 3,000to 15,000 centipoises at temperatures of about 190°C.

In certain embodiments, where additional layer 40 acts as a backinglayer, additional layer 40 may be impermeable to liquid, but permeableto gas, which allows the wound and the skin to which the bandage andtape 10 of the present invention is adhered to breathe. In oneembodiment, where additional layer 40 acts as a backing layer,additional layer 40 may have pores of such a size that will allow onlythe passage of gases, which have molecules of extremely small size.

Finally, where additional layer 40 acts as a backing layer, additionallayer 40 may be perforated for still further ventilation of the skin. Incertain such embodiments, perforations may be circular in area and havea range of diameters, such as from about 0.1 to about 0.8 millimeters.In certain other embodiments, however, where additional layer 40 acts asa backing layer, additional layer 40 may, when necessary, be totallyimpermeable to gases.

The present invention is further described by the following exampleswhich are presented for purposes of illustration and comparison.

It is to be understood that at least some of the figures anddescriptions of the invention have been simplified to focus on elementsthat are relevant for a clear understanding of the invention.

Further, to the extent that any method does not rely on the particularorder of steps set forth herein, the particular order of the stepsshould not be construed as limitation on the claims. The claims directedto any such method of the present invention should not be limited to theperformance of their steps in the order written, and one skilled in theart can readily appreciate that the steps may be varied and still remainwithin the spirit and scope of the present invention.

Embodiments of the Present Invention

-   -   1. A dressing comprising:    -   a layer of non-cellulosic material having:        -   (i) a length direction (L), a width direction (W), and a            thickness direction (T) respectively defining axes in three            mutually orthogonal directions, the length direction (L) and            the width direction W defining a horizontal plane (“the LW            plane”), and the thickness direction (T) defining an up-down            direction or a vertical direction relative to the LW plane,            the layer of material having a thickness taken in the            thickness direction; and        -   (ii) a plurality of material free regions, each of the            material free regions extending through the thickness of at            least a portion of the layer of material and the plurality            of the material free regions being arranged in the form of a            pattern of concentric slitted annuli having a center            point (P) in the LW plane, the pattern of concentric slitted            annuli having, relative to center point P, a radially            innermost concentric annulus and a radially outermost            concentric annulus, the innermost and the outermost            concentric annuli respectively having the shortest and the            longest diameters,    -   wherein the plurality of the material free regions is arranged        end to end, separated by a plurality of spatial intervals, such        that any material free region ln located in any concentric        annulus I subtends a non-zero valued angle, con, at the center        point P, where n represents the number identifying a material        free region in an annulus having material free regions arranged        numerically consecutively in such annulus,    -   wherein the sum of the non-zero valued angles subtended by the        plurality of the material free regions at the center point P,        within any one of the concentric annuli, is less than 360        degrees, and    -   wherein the material free regions of any one of the concentric        annuli are in a radially staggered relation with respect to the        material free regions in any adjacent inner and/or adjacent        outer concentric annulus.    -   2. The dressing of embodiment 1 further including one or more        intervening concentric annuli disposed between the innermost and        outermost concentric annuli.    -   3. The dressing of embodiments 1 and/or 2, wherein any of the        one or more intervening concentric annuli has a larger diameter        than the diameter of any adjacent inner concentric annulus with        respect to the intervening concentric annulus.    -   4. The dressing of any one or combination of the preceding        embodiments, wherein any material free region of any radially        concentric annulus has an axis of symmetry bisecting the angle        subtended by the material free region at the center point P.    -   5. The dressing of any one or combination of the preceding        embodiments, wherein any material free region of the radially        outermost and/or innermost concentric annulus has an axis of        symmetry bisecting the angle subtended by the material free        region at the center point P.    -   6. The dressing of any one or combination of the preceding        embodiments, wherein:        -   (a) any material free region ln further has an axis of            symmetry that bisects the non-zero valued angle α_(ln);        -   (b) any material free region Kn located in any concentric            annulus K that is adjacent to concentric annulus I and            proximate to material free region ln, subtends a non-zero            valued angle α_(Kn) at the center point P and has an axis of            symmetry that bisects the non-zero valued angle α_(Kn);        -   (c) the axis of symmetry of the material free region ln is            staggered by an angle φ from the axis of symmetry of the            material free region Kn; and        -   (d) the angle φ has a value that falls within a range            specified by the equation: 0°<φ<(α_(ln)+α_(Kn)).    -   7. The dressing of any one or combination of the preceding        embodiments, wherein the axis of symmetry of any material free        region of the radially innermost concentric annulus is radially        staggered from the axis of symmetry of any proximate material        free regions located in the radially outermost concentric        annulus, by an angle φ that has a value ranging from about 5° to        about 40°.    -   8. The dressing of any one or combination of the preceding        embodiments, wherein the axis of symmetry of any material free        region in any one of the concentric annuli is radially staggered        from the axis of symmetry of any proximate material free regions        located in any adjacent radially inner or outer concentric        annulus with respect to the concentric annulus by an angle φ        that has a value ranging from about 5° to about 30°.    -   9. The dressing of any one or combination of the preceding        embodiments, wherein the innermost concentric annulus has a        diameter ranging from about 0.125″ to about 3.5″.    -   10. The dressing of any one or combination of the preceding        embodiments, wherein the outermost concentric annulus has a        diameter ranging from about 0.125″ to about 0.25″.    -   11. The dressing of any one or combination of the preceding        embodiments, wherein the innermost concentric annulus has a        diameter ranging from about 0.125 to about 0.5″ and the        outermost concentric annulus has a diameter ranging from about        0.5″ to about 1″.    -   12. The dressing of any one or combination of the preceding        embodiments, wherein the innermost concentric annulus has a        diameter of about 0.125″.    -   13. The dressing of any one or combination of the preceding        embodiments, wherein the outermost concentric annulus has a        diameter of about 0.5″.    -   14. The dressing of any one or combination of the preceding        embodiments, wherein the innermost concentric annulus has a        diameter of about 0.125″ and the outermost concentric annulus        has a diameter of about 0.5″.    -   15. The dressing of any one or combination of the preceding        embodiments, wherein each concentric annulus has a concentric        centerline.    -   16. The dressing of any one or combination of the preceding        embodiments, wherein the pattern of concentric slitted annuli        has equal radial spacing between neighboring concentric        centerlines of successive pairs of neighboring concentric        annuli.    -   17. The dressing of any one or combination of the preceding        embodiments, wherein any pair of neighboring concentric        centerlines of a pair of neighboring concentric annuli is        separated by a radial spacing that varies among different pairs        of neighboring concentric centerlines of successive pairs of        neighboring concentric annuli of the pattern of concentric        slitted annuli.    -   18. The dressing of any one or combination of embodiments 1-15,        wherein the pattern of concentric slitted annuli has a radial        spacing between pairs of neighboring concentric centerlines of        neighboring concentric annuli that increases radially outwardly        from the center point P.    -   19. The dressing of any one or combination of embodiments 1-15,        wherein the pattern of concentric slitted annuli has a radial        spacing between pairs of neighboring concentric centerlines of        neighboring concentric annuli that decreases radially outwardly        from the center point P.    -   20. The dressing of any one or combination of embodiments 1-15,        wherein the pattern of concentric slitted annuli has a radial        spacing between each pair of neighboring concentric centerlines        of successive pairs of neighboring concentric annuli that varies        among different pairs of neighboring concentric annuli.

1 21. The dressing of any one or combination of embodiments 1-15,wherein any pair of adjacent concentric annuli is spaced apart radiallyby a distance that is the difference between the respective radialdistances of the adjacent concentric annuli from the center point P.

-   -   22. The dressing of any one or combination of the preceding        embodiments, wherein the layer of material is expansible in the        thickness direction thereof    -   23. The dressing of any one or combination of embodiments 1-21,        wherein the layer of material is resiliently expansible in the        thickness direction in response to any force that is applied to        the portion of the dressing having the pattern of concentric        slitted annuli, whereby the resilient expansion of the layer of        material is a percentage that is proportional to the magnitude        of the force being applied thereto.    -   24. The dressing of any one or combination of the preceding        embodiments, wherein each of the plurality of spatial intervals        separating the plurality of material free regions within any        given concentric annulus has a size that has a minimal value        within the innermost concentric annulus and increases in value        with each successive radially outer concentric annulus to its        maximum value within the outermost concentric annulus of the        pattern of concentric slitted annuli.    -   25. The dressing of any one or combination of the preceding        embodiments, wherein any spatial interval within any given        concentric annulus subtends an angle θ at the center P.    -   26. The dressing of embodiment 25, wherein the angle θ has a        value that ranges from about 3° to 20°.    -   27. The dressing of any one of or combination of embodiments 25        and/or 26, wherein the angle θ has from about 6° to 20°.    -   26. A dressing comprising:    -   a. a layer of material having:        -   (i) a length direction (L), a width direction (W), and a            thickness direction (T) respectively defining axes in three            mutually orthogonal directions, the length direction (L) and            the width direction W defining a horizontal plane (“the LW            plane”), and the thickness direction (T) defining an up-down            direction or a vertical direction relative to the LW plane,            the layer of material having a thickness taken in the            thickness direction; and        -   (ii) a plurality of material free regions, each of the            material free regions extends through the thickness of the            layer of material and the plurality of the material free            regions is arranged in the form of a pattern of concentric            slitted annuli having a center point (P) in the LW plane,            the pattern of concentric slitted annuli having, relative to            center point P, a radially innermost concentric annulus and            a radially outermost concentric annulus, the innermost and            the outermost concentric annuli respectively having the            shortest and the longest diameters; and    -   b. a releasable liner releasably contacting the layer of        material;    -   wherein the material free regions are arranged end to end,        separated by spatial intervals, such that any material free        region ln located in any concentric annulus I subtends a        non-zero valued angle α_(ln) at the center point P where n        represents the number identifying a material free region in an        annuli having material free regions arranged numerically        consecutively in such annuli,    -   wherein the sum of the non-zero valued angles subtended by the        plurality of the material free regions at the center point P, in        any one of the concentric annuli, is less than 360 degrees, and    -   wherein the material free regions of any one of the concentric        annuli are in a radially staggered relation with the material        free regions in any adjacent inner and/or adjacent outer        concentric annulus.    -   27. The dressing of embodiment 26, wherein any material free        region ln further has an axis of symmetry that bisects the        non-zero valued angle α_(ln).    -   28. The dressing of any one or combination of embodiments 26        and/or 27, wherein any material free region Kn located in any        concentric annulus K that is adjacent to concentric annulus I        and proximate to material free region ln subtends a non-zero        valued angle α_(Kn) at the center point P and has an axis of        symmetry that bisects the non-zero valued angle α_(Kn), wherein        the axis of symmetry of the material free region ln and the axis        of symmetry of the material free region Kn are staggered        relative to one another by an angle φ that has a value falling        within a range specified by the equation: 0°<φ<(α_(ln)+α_(Kn)).    -   29. The dressing of embodiment 26, wherein the angle φ has a        value ranging from about 5° to about 40°.    -   30. The dressing of embodiment 26, wherein the angle φ has a        value ranging from about 5° to about 30°.    -   31. The dressing of any one or combination of embodiments 26-30,        wherein each of the angles α_(ln) and α_(Kn) has a value ranging        from about 20° to about 177°.    -   32. The dressing of any one or combination of embodiments 26-31,        wherein each of the angles α_(ln) and α_(Kn) has a value ranging        from about 20° to about 90°.    -   33. The dressing of any one or combination of embodiments 26-32,        wherein each of the angles α_(ln) and α_(Kn) has a value ranging        from about 20° to about 60°.    -   34. The dressing of any one or combination of embodiments 26-33,        wherein each of the angles α_(ln) and α_(Kn) has a value ranging        from about 30° to about 60°.    -   35. A dressing comprising:        -   a.) a layer of material having top and bottom surfaces, the            layer of material having a thickness direction (T) and            configured to be resiliently freely expandable in the            thickness direction T by any force applied in the thickness            direction T from a skin surface at or around an area covered            or contacted by the dressing,        -   the layer of material having mutually orthogonal length (L)            and width (W) directions jointly defining a horizontal plane            (“the LW plane”) of the layer of material, the LW plane            being orthogonal to the thickness direction T and the layer            of material having a thickness taken in the thickness            direction T;        -   the layer of material includes a concentric pattern of            annuli having a center point P and configured such that it            is resiliently freely expandable in the thickness direction            T of the layer of material between an initial substantially            flat configuration in the LW plane of the layer of material            and an expanded configuration in the thickness direction T            of the layer of material,        -   the concentric pattern of annuli includes a plurality of            material free regions that are freely changeable between an            initial closed configuration and an open configuration, and            the material free regions being arranged such that when a            force is applied in the thickness direction T, from a skin            surface at or around an area covered or contacted by the            dressing, one or more of the material free regions freely            change from the initially closed configuration to the open            configuration;    -   b.) an adhesive on at least one of the surfaces of the layer of        material;    -   wherein the concentric pattern of annuli and the layer of        material expand in the thickness direction T to an expanded        configuration,    -   wherein once the force is no longer being applied on the layer        of material, the one or more material free regions freely return        to their initially closed configuration,    -   causing the pattern of concentric slitted annuli to freely        return to its initial substantially flat configuration in the LW        plane of the material layer.    -   36. The dressing of embodiment 35, wherein the plurality of the        material free regions is arranged end to end, separated by        spatial intervals, such any material free region ln located in        any concentric annulus I subtends a non-zero valued angle α_(ln)        at the center point P, where n represents the number identifying        a material free region in an annuli having material free regions        arranged numerically consecutively in such annuli.    -   37. The dressing of any one or combination of embodiments 35 and        36, wherein the sum of the non-zero valued angles subtended by        the plurality of the material free regions at the center point        P, within any one of the concentric annuli, is less than 360        degrees.    -   38. The dressing of any one or combination of embodiments 35-37,        wherein the material free regions of any one of the concentric        annuli are in a radially staggered relation with respect to the        material free regions in any adjacent inner and/or adjacent        outer concentric annulus.    -   39. The dressing of any one or combination of embodiments 36-38,        wherein material free region ln has an axis of symmetry that        bisects the non-zero valued angle α_(ln).    -   40. The dressing of embodiment 39, wherein any material free        region Kn located in any concentric annulus K that is adjacent        to concentric annulus I and proximate to material free region        ln, not only subtends a non-zero valued angle α_(kl) at the        center point P, but also has an axis of symmetry that bisects        the non-zero valued angle α_(Kn), wherein the axis of symmetry        of the material free region ln and the axis of symmetry of the        material free region Kn are staggered relative to one another by        an angle φ that has a value falling within a range specified by        the equation: 0°<φ<(α_(ln)+α_(Kn)).    -   41. The dressing of embodiment 40, wherein the angle φ has a        value ranging from about 5° to about 40°.    -   42. The dressing of any one or combination of embodiments 40        and/or 41, wherein the angle φ has a value ranging from about 5°        to about 30°.    -   43. The dressing of embodiment 40, wherein each of angles α_(ln)        and α_(Kn) has a value ranging from about 20° to about 177°.    -   44. The dressing of any one or combination of the preceding        embodiments, wherein each of angles α_(ln) and α_(Kn) has a        value ranging from about 20° to about 90°.    -   45. The dressing of any one or combination of the preceding        embodiments, wherein each of angles α_(ln) and α_(Kn) has a        value ranging from about 20° to about 60°.    -   46. The dressing of any one or combination of the preceding        embodiments, wherein each of angles α_(ln) and α_(Kn) has a        value ranging from about 30° to about 60°.    -   47. A dressing comprising:    -   a. one or more layers comprising a layer of material having:        -   (i) a length direction (L), a width direction (W), and a            thickness direction (T) respectively defining axes in three            mutually orthogonal directions, the length direction (L) and            the width direction W defining a horizontal plane (“the LW            plane”), and the thickness direction (T) defining an up-down            direction or a vertical direction relative to the LW plane,            the layer of material having a thickness taken in the            thickness direction; and        -   (ii) a plurality of material free regions, each of the            material free regions extends through the thickness of the            layer of material and the plurality of the material free            regions is arranged in the form of a pattern of concentric            slitted annuli having a center point (P) in the LW plane,            the pattern of concentric slitted annuli having, relative to            center point P, a radially innermost concentric annulus and            a radially outermost concentric annulus, the innermost and            the outermost concentric annuli respectively having the            shortest and the longest diameters; and    -   b. a releasable liner releasably contacting the one or more        layers,    -   wherein the material free regions are arranged end to end,        separated by spatial intervals, such that any material free        region ln located in any concentric annulus I subtends a        non-zero valued angle α_(ln) at the center point P where n        represents the number identifying a material free region in an        annuli having material free regions arranged numerically        consecutively in such annuli.

What is claimed is:
 1. A dressing comprising: a layer of non-cellulosicmaterial having: (i) a length direction (L), a width direction (W), anda thickness direction (T) respectively defining axes in three mutuallyorthogonal directions, the length direction (L) and the width directionW defining a horizontal plane (“the LW plane”), and the thicknessdirection (T) defining an up-down direction or a vertical directionrelative to the LW plane, the layer of material having a thickness takenin the thickness direction; and (ii) a plurality of material freeregions, each of the material free regions extending through thethickness of at least a portion of the layer of material and theplurality of the material free regions being arranged in the form of apattern of concentric slitted annuli having a center point (P) in the LWplane, the pattern of concentric slitted annuli having, relative tocenter point P, a radially innermost concentric annulus and a radiallyoutermost concentric annulus, the innermost and the outermost concentricannuli respectively having the shortest and the longest diameters,wherein the plurality of the material free regions is arranged end toend, separated by a plurality of spatial intervals, such that anymaterial free region ln located in any concentric annulus I subtends anon-zero valued angle, con, at the center point P, where n representsthe number identifying a material free region in an annulus havingmaterial free regions arranged numerically consecutively in suchannulus, wherein the sum of the non-zero valued angles subtended by theplurality of the material free regions at the center point P, within anyone of the concentric annuli, is less than 360 degrees, and wherein thematerial free regions of any one of the concentric annuli are in aradially staggered relation with respect to the material free regions inany adjacent inner and/or adjacent outer concentric annulus.
 2. Thedressing of claim 1 further including one or more intervening concentricannuli disposed between the innermost and outermost concentric annuli.3. The dressing of claim 2, wherein any of the one or more interveningconcentric annuli has a larger diameter than the diameter of anyadjacent inner concentric annulus with respect to the interveningconcentric annulus.
 4. The dressing of claim 1 wherein any material freeregion of any radially concentric annulus has an axis of symmetrybisecting the angle subtended by the material free region at the centerpoint P.
 5. The dressing of claim 1, wherein: (a) any material freeregion ln further has an axis of symmetry that bisects the non-zerovalued angle α_(ln); (b) any material free region Kn located in anyconcentric annulus K that is adjacent to concentric annulus I andproximate to material free region ln, subtends a non-zero valued angleα_(Kn) at the center point P and has an axis of symmetry that bisectsthe non-zero valued angle α_(Kn); (c) the axis of symmetry of thematerial free region ln is staggered by an angle φ from the axis ofsymmetry of the material free region Kn; and (d) the angle φ has a valuethat falls within a range specified by the equation:0°<φ<(α_(ln)+α_(Kn)).
 6. The dressing of claim 4, wherein the axis ofsymmetry of any material free region of the radially innermostconcentric annulus is radially staggered from the axis of symmetry ofany proximate material free regions located in the radially outermostconcentric annulus, by an angle φ that has a value ranging from about 5°to about 40°.
 7. The dressing of claim 4, wherein the axis of symmetryof any material free region in any one of the concentric annuli isradially staggered from the axis of symmetry of any proximate materialfree regions located in any adjacent radially inner or outer concentricannulus with respect to the concentric annulus by an angle φ that has avalue ranging from about 5° to about 30°.
 8. The dressing of claim 1,wherein the innermost concentric annulus has a diameter ranging fromabout 0.125″ to about 3.5″.
 9. The dressing of claim 1, wherein theoutermost concentric annulus has a diameter ranging from about 0.125″ toabout 0.25″.
 10. The dressing of claim 1, wherein the innermostconcentric annulus has a diameter ranging from about 0.125 to about 0.5″and the outermost concentric annulus has a diameter ranging from about0.5″ to about 1″.
 11. The dressing of claim 1, wherein each concentricannulus has a concentric centerline.
 12. The dressing of claim 11,wherein the pattern of concentric slitted annuli has equal radialspacing between neighboring concentric centerlines of successive pairsof neighboring concentric annuli.
 13. The dressing of claim 11, whereinany pair of neighboring concentric centerlines of a pair of neighboringconcentric annuli is separated by a radial spacing that varies amongdifferent pairs of neighboring concentric centerlines of successivepairs of neighboring concentric annuli of the pattern of concentricslitted annuli.
 14. The dressing of claim 13, wherein the pattern ofconcentric slitted annuli has a radial spacing between pairs ofneighboring concentric centerlines of neighboring concentric annuli thatincreases radially outwardly from the center point P.
 15. The dressingof claim 13, wherein the pattern of concentric slitted annuli has aradial spacing between pairs of neighboring concentric centerlines ofneighboring concentric annuli that decreases radially outwardly from thecenter point P.
 16. The dressing of claim 11, wherein the pattern ofconcentric slitted annuli has a radial spacing between each pair ofneighboring concentric centerlines of successive pairs of neighboringconcentric annuli that varies among different pairs of neighboringconcentric annuli.
 17. The dressing of claim 1, wherein any pair ofadjacent concentric annuli is spaced apart radially by a distance thatis the difference between the respective radial distances of theadjacent concentric annuli from the center point P.
 18. The dressing ofclaim 1, wherein each of the plurality of spatial intervals separatingthe plurality of material free regions within any given concentricannulus has a size that has a minimal value within the innermostconcentric annulus and increases in value with each successive radiallyouter concentric annulus to its maximum value within the outermostconcentric annulus of the pattern of concentric slitted annuli.
 19. Thedressing of claim 1, wherein any spatial interval within any givenconcentric annulus subtends an angle θ at the center P and furtherwherein the angle θ has a value that ranges from about 3° to 20°.